diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index c5c461c..934b2b6 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -7,7 +7,7 @@ jobs:
     name: build (${{ matrix.ruby }} / ${{ matrix.os }})
     strategy:
       matrix:
-        ruby: [ '3.0', 2.7, 2.6, 2.5, head ]
+        ruby: [ '3.0', 2.7, 2.6, 2.5, 2.4, 2.3, 2.2, 2.1, head ]
         os: [ ubuntu-latest, macos-latest, windows-latest ]
     runs-on: ${{ matrix.os }}
     steps:
@@ -22,7 +22,7 @@ jobs:
       with:
         ruby-version: ${{ matrix.ruby }}
     - name: Run test
-      run: rake test
+      run: bundle install && bundle exec rake test
     - id: build
       run: |
         rake build